The present invention relates to the decontamination arts including the sterilization arts. It finds particular application in conjunction with the decontamination of medical devices, especially medical devices such as endoscopes and other devices having channels or lumens that must be decontaminated after use.
Sterilization is typically defined as the absence of all life forms including bacterial endospores which are the living organisms most resistant to known sterilants. Disinfection, by distinction, only connotes the absence of pathogenic life forms. Herein, the general term, decontamination, will be used to describe both disinfection and sterilization.
Endoscopes and similar medical devices having channels or lumens formed therethrough are being used on an ever increasing basis in the performance of medical procedures. The popularity of these devices has led to calls for improvements in the decontamination of these devices between use, both in terms of the speed of the decontamination and the effectiveness of the decontamination. One drawback associated with many known endoscope decontamination devices is their reliance on reusable glutaraldehyde or the like as a liquid decontaminant solution. While glutaraldehyde is generally effective for disinfection, sterilization with glutaraldehyde can take 10 to 12 hours which is too long in today's healthcare facilities. Another drawback to glutaraldehyde systems is that they sterilize without cleaning, i.e., they leave sterile biological waste matter on the medical instruments.
Another drawback associated with many known decontamination devices is their lack of a decontaminated rinse liquid. Many known decontamination devices are concerned only with cleaning and disinfecting the devices and consequently rely on unfiltered "tap" water for rinsing. Even those that filter or otherwise decontaminate the rinse liquid often do not decontaminate the rinse liquid flow paths between the source of rinse liquid and the decontamination basin under the incorrect assumption that these apparently closed rinse liquid flow paths cannot become contaminated. Thus, with these devices, it is possible for microorganisms to be reintroduced onto the medical device from the rinse liquid. One known endoscope sterilizer does provide a sterile rinse and rinse liquid flow path (STERIS SYSTEM 1.RTM., STERIS Corporation, Mentor, Ohio). However, it would be desirable to include additional features in conjunction with the sterile rinse and sterile rinse flow paths of this unit.
Prior medical instrument decontamination devices do not include a simple and effective means for accurately delivering a select charge of both detergent concentrate and decontaminant concentrate as needed to form a cleaning solution and a decontamination solution, respectively. Instead, many prior devices rely upon a large tank to hold a reusable decontaminant such as glutaraldehyde and rely upon tank of detergent that must be refilled. The need to refill these tanks periodically decreases efficiency and also puts an operator in contact with decontaminant and detergent liquid and vapors. Further, glutaraldehyde is an environmentally hazardous material that needs to be chemically deactivated. Disposal or reprocessing of diluted or contaminated glutaraldehyde is inconvenient and costly.
Furthermore, with these systems, it is possible for the detergent tank or the decontaminant tank to run dry without the knowledge of the machine operator. Also, it is not always possible to verify that the detergent or decontaminant has actually been properly and accurately dispensed into the decontamination basin. It would be desirable to provide a decontamination apparatus that simply and accurately dispenses a select dose of detergent concentrate and decontaminant concentrate as needed, without requiring tanks to be refilled and without exposing an operator to detergents and decontaminants. It would also be desirable to provide such a system which reduces the possibility that an incorrect amount of detergent or decontaminant will be dispensed.
The present application is therefore directed to a method and apparatus which overcomes these problems and others while providing better overall decontamination results and efficiency.